Back-pressure valve mechanism



p 6, 1930. R. H. SCHNEIDER BACK PRESSURE VALVE MECHANISM Filed Jan. 25, 1929 2 v 2 4 WW H g W/ g r z 5 Patented Sept. 16, 1930 UNITED STATES RUSSELL H. SCHNEIDER, OF DAYTON, OHIO BACK-PRESSURE VALVE MECHANISM Application filed January 25, 1329 Serial No. 335,018.

a novel type of valve mechanism specially.

designed to be attached to the lower end of a screen set in a well bore and provided for the purpose of preventing the inflow of fluid I from the bore beneath into the screen but which will open downwardly to permit water to be forced through the wash pipe and on' through the valve and to return up around the screen to wash the screen preparatory to bringing in the well in which the screen is set; and the valve mechanism embodies a novel type of seat and valve of such construction that the valve, when seated, will always form a close fit with the seat to prevent leakage past the valve.

vide a valve mechanism of the character described whose co-acting parts will not readily wear so as to permit leakage of the valve.

A further feature of the invention is to provide a valve mechanism of the character described which is of simple construction, may be cheaply produced and which is very durable.

With the above and other objects in view this invention has particular relation to certain novel features of construction, operation and arrangement of parts an example of whichis given in this specification and illustrated in the accompanying drawings, where- Figure 1 shows a vertical sectional view of the valve mechanism, and

Figure 2 shows a cross sectional View thereof, taken on the line 22 of Figure 1.

Referring now more particularly to the drawings, wherein like numerals of reference designate similar parts in each of the figures the numeral 1 designates a tubular valve body which is attached to the lower end of the well screen 2. In this valve body there is a tubular nipple 3 whose upper end has an external, annular, externally threaded flange 4 which is screwed into the valve body, the upper end of this nipple is flared forming a wash pipe seat 5. The lower end of Another object of the invention is to prothis nipple has an inside valve seat 6 which is circular in form and whose upper end is tapered, or"converges inwardly and upwardly.

Attached to the lower end of the valve body 1 thereis a guide plug 7 whose lower end is rounded off and which serves to guide the screen down the well bore in setting the screen. This guide plug has an axial bore 8 extending from end to end thereof and whose lower end is reduced forming an internal annular shoulder 9. The upper end of the guide plug is reduced and thus spaced inwardly from the valve body forming a valve guide 10. The lower end of this guide has the radial perforations 11 and working in said guide there is the inverted cup shaped valve 12 whose upper end is formed to conform to the contour of, and to closely fit within the seat 6. This valve is seated on the coil spring 13 which is located in the bore 8 and rests on the shoulder 9, and this spring normally holds the valve seated against the seat 6. The opposing ends of the nipple 3 and valve guide 10 are spaced apart, as shown, to provide a fluid passageway between them.

In use the valve mechanism is attached to the lower end of a well screen which is then let down into a well bore. Before the well is brought in it is common practice to wash the screen to remove all clogging material therefrom. This is accomplished by lowering a wash pipe down until its lower end rests'on the seat 5 and the washing fluid is forced down through said wash pipe and forces the valve 12 open and passes on down and out between the nipple 3 and guide 10 and then in through the perforations 11 and down through the bore 8 and up around the screen.

When the well is washed the wash pipe is withdrawn and the valve 12 seats to prevent the inflow of fluid into the screen from beneath.

The upper end of the valve 12 and the seat 6 cooperating therewith are so formed that there will be a large area of contact between them, so as to minimize leakage between them, and the upper end of the valve being tapered it will readily enter thevalve seat and as the valve enters said seat, in closing,

it will displace, orforce to one side, any foreign matter that-might-tend to collect in i the seat, and such foreign matter or detritus will not be liable to be engaged between said valve and seat and hold thevalve open. The free end of the seat Will-be gradually cut away, or flared, by the gritty fluid but the inwardly converging, or beveled, portion of the seat will still fit perfectlyiwiththe free- 7 end of the valve and thus efiectively prevent leakage.

A preferred form ofbthevalve mechanism has been shownanddescribed but it isobvious that. mechanicalchanges may be 'made v therein and equivalents"substituted"for the L the principle ofthein- I parts shown within vention.

Whatlclaim is:

valve guide at the upper endof the plug,

.a cylindrical valve fittedand slidably mounted in said guide, a yieldable member in the '7 plug on which said valve is "mounted, said guide having an opening beneath the valve,

a n'annula'r valve seat fixed in the valve body and spaced above the valve guide WithWhiCll; V

7 said valve cooperates, said seat having a sleeveplike guide. depending therefrom in whicl the valve is adapted to fit.

seatin said body spaced above said guide M and withfiwhich thevaIVe cOoperates, the'free 7 endioif the-valve being beveled and the seat 7 being formed to conform to thefcontour of ,andto receive the beveled end of said valve, there beinga sleeve depending from said seat in which the valve fit siwhen seated;

In testimony na'm 1, A back pressure valve mechanism ineluding atubular valve body, a guide plug 1 at the lower end thereof said plug having a f fluid passageway:therethrough; .a sleeve like whereof I have signed aesse H. soH in RQ CERTIFICATE OF CORRECTION.

Patent No. 1,775,833. Granted September 16, 1930, to

RUSSELL H. SGHNEI DER.

it is hereby certified that errcr appears in the above numbered patent ction as follows: In the grant, and in the heading to the printed requiring eerre specification, the residence of the patentee was erroneously written and printed as "Dayton, Ohio, whereas said residence shcriici have been written and printed as Dayten, Texas; and that the said Letters Patent shenid be read with this correction therein that the same may conform to the recerd of the case in the Patent Office.

Signed and sealed this 18th day of Ncvember, A. D. 1930.

M. J. Moore,

(Seal) Acting Gemmissicner of Patents. 

